This invention relates to the field of hydrocarbon gas treatment systems and in particular to mobile gas treatment systems that remove hydrocarbon gases from air discharged from a mobile source.
Prior art mobile gas treatment systems have been aimed at purifying the exhaust emissions of an automobile engine. No mobile gas treatment system has addressed the problem of removing hydrocarbon gases from large quantities of air discharged from a mobile source.
The problems with prior art mobile gas treatment systems is that they are limited to treating exhaust emissions from automobiles, and they cannot process the large quantities of air discharged from a mobile source the size of a vacuum truck.
Examples of prior art devices include those disclosed in the following United States Patents:
U.S. Pat. No. 4,784,676 discloses a disposable vacuum cleaner bag containing water that functions as a dust removal media. One problem with this device is that it cannot remove hydrocarbon gases from air. Another problem is that it cannot handle the large quantities of air and gas discharged from a vacuum truck.
U.S. Pat. No. 4,774,974 discloses a system for removing toxic particulate materials from surfaces to a van body. The problem with this device is that it cannot remove gas from air.
U.S. Pat. No. 4,588,535 discloses a combustion gas treatment system that directs hot combustion gases into vertical ducts where a washing liquid from sprinklers at the upper end of the ducts, remove solid and soluble components while simultaneously cooling the gas.
U.S. Pat. No. 4,540,162 discloses a precious metals refining process whereby gases or vapors that result from acid action on the precious metals, are purified by utilizing a series of containers having baffle plates and water therein.
U.S. Pat. No. 4,251,486 discloses a system for decomposing injurious gases to make them harmless by utilizing a decomposition tower having an internal aqueous solution at the bottom with circulating means and nozzles to spray the aqueous solution into contact with the injurious gas. The injurious gas is decomposed and the decomposition products are washed down into the aqueous solution. The remaining injurious gas which has not been decomposed is directed into first and secondary reaction vessels having the same decomposition spray as the decomposition tower whereupon all remaining gases are rendered harmless.
U.S. Pat. No. 3,998,613 discloses an apparatus for removal of sulfur dioxide and particulate matter from hot flue gases from a furnace. Circulating water in the apparatus combines with the flue gas thereby removing sulfur dioxide and particulates and simultaneously cooling the gas.
U.S. Pat. No. 3,984,219 discloses an engine purifier muffler that utilizes polyurethane foam and water to filter engine exhaust gases with the internal water level above the input line to attenuate the noise.
U.S. Pat. No. 3,922,152 discloses a multiple stage filter for removing pollutants from exhaust gases. Each stage has a tubular coil with a plurality of holes along the upper side of the coil to allow gases to rise from the coil into a layer of water and sandstone. The sandstone layer has large stones at the bottom and progressively smaller stones toward the top of the layer. The filtered gas is then directed through the remaining stages which have the same design as the first stage. The filtered gas is then discharged to the atmosphere after passing through the final stage.
U.S. Pat. No. 3,793,807 discloses a process for purifying exhaust emissions from an automobile engine that directs the exhaust gas through a series of small tanks containing a mixture of saline solution and a solution of tri-sodium phosphate.